青稞及其制品的体内外淀粉消化特性研究

淀粉是青稞中的主要成分,其消化速率及程度直接影响餐后血糖反应。通过探究青稞及其制品体外淀粉消化特性,同时参照国际标准办法,招募12名健康志愿者,测定4种青稞制品的体内血糖生成指数(GI)。结果表明:青稞熟粉的淀粉消化速率显著低于小麦熟粉,蒸煮和挤压处理均可显著增加青稞及小麦中快消化淀粉(RDS)质量分数,降低抗性淀粉质量分数。青稞制品的GI值从大到小依次为青稞馒头(70±11)、青稞鲜湿面(60±13)、青稞挂面(51±11)、青稞炒面(33±14)。相关性分析结果表明,GI值与RDS呈极显著正相关(R=0.733,P=0.007)。体内外实验均表明:不同加工方式可显著影响青稞制品的消化特性,消费者有必要根据自身的健康状况选择合适的产品。青稞挂面及青稞炒面属于低GI食品,有利于血糖控制人群或糖尿病病人食用。

Study on in Vitro and in Vivo Starch Digestive Characteristics of Qingke Barley and Its Products

Starch is the main component of Qingke barley, its digestion rate and degree directly affects the postprandial blood glucose response. Therefore, in vitro starch digestibility of Qingke barley and it''s products were investigated in this study. Meanwhile, 12 healthy volunteers were recruited to measure the glycemic index (GI) of 4 kinds of Qingke barley products according to international standard methods. The results showed that the starch digestibility rate of the cooked Qingke barley flour was significantly lower than that of cooked wheat flour. Cooking and extrusion significantly increased rapidly digestible starch (RDS) and decreased resistant starch in both Qingke barley and wheat. GI values of Qingke barley steamed bread, Qingke barley fresh noodles, Qingke barley noodles and Qingke barley fried noodles were 70±11,60±13,51±11, and 33±14, respectively. The results of correlation analysis showed that GI value was significantly positively correlated with RDS(R=0.733, P=0.007). In vitro and in vivo tests both suggested that different processing techniques could affect the digestive characteristics of Qingke barley products. It is necessary for consumers to select appropriate products according to their own health status. Qingke barley noodles and Qingke barley fried noodles were classified as low GI food, which were conducive to the glycemic control crowd or diabetic patients to eat.